This change improves some IncompatibleClassChangeError messages by printing the classes involved and adds tests for the messages.

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If a class is loaded requiring an interface that's already loaded as class:

Before:

"Implementing class"

After:

"Class test.ICC3_B can not implement test.ICC3_A, because it is not an interface"

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If a class is loaded requiring a super class that has already been loaded as interface:

Implemented a test. Message left unchanged:

"class test.ICC4_B has interface test.ICC4_iA as super class"

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If an interface method is called but the class of the object at runtime does not implement the interface:

There was no message before.

After:

"Receiver class test.ICC5_B does not implement the interface test.ICC5_B defining the method to be called"

No tests implemented for this message